Current status of the JAEA's Fukushima R&D bases for the decommissioning of the Fukushima Daiichi Nuclear Power Station

Shobu, Nobuhiro; Ooka, Makoto; Nakai, Toshiro; Nakayama, Shinichi

no journal, , 

The Japan Atomic Energy Agency (JAEA) is operating and constructing R&D bases at the coastal area of the Fukushima Prefecture for the decommissioning of the Fukushima Daiichi Nuclear Power Station (NPS) of the Tokyo Electric Power Company Holdings, Inc. (TEPCO). This paper reports current status of the R&D bases.

Visualization of radioactive substances by integrating radiation measurement, remote technology, and 3-D optical measurement

Sato, Yuki; Terasaka, Yuta; Kaburagi, Masaaki; Tanifuji, Yuta; Torii, Tatsuo

no journal, , 

Application of ICP-MS to analysis of samples from 1F site at Radioactive Material Analysis and Research Facility

Do, V. K.; Horita, Takuma; Miura, Katsue; Iwasaki, Maho

no journal, , 

Radioactive Material Analysis and Research Facility has been recently established to support the analysis of samples including fuel debris and radioactive wastes from the decommissioning of Fukushima Daiichi Nuclear Power Station (1F). ICP-MS is considered as a potential analytical tool for long-lived nuclides in fuel debris because of its superior sensitivity. Moreover, the use of ICP-MS is aimed to increase the analysis capacity, which make possible to repeat measurements in order to obtain precise results and to reduce exposed dose of analysts because ICP-MS is much more rapid than radiometric methods. Employing latest advanced technologies, a triple quadrupole ICP-MS, Agilent 8900 (ICP-QQQ-MS), enables to suppress the isobaric interference. In this presentation, we report some demonstrative separations of difficult-to-measure nuclides using the ICP-QQQ-MS system. The obtained results indicate that the separations are possible with suitable reaction gases.

Study on wet waste storage; Irradiation behavior of carbonate slurry and wet zeolite

Yamagishi, Isao; Motooka, Takafumi

no journal, , 

Highly radioactive wastes such as carbonate slurry and zeolite are generated from the contaminated water treatment system at Fukushima Daiichi Nuclear Power Station. We have studied radiolytic gas generation in wet wastes for their safe storage. Carbonate slurry or wet zeolite as a simulated waste was irradiated by -ray. Radiolytic gas generation resulted in the slurry expansion and supernatant separation from the slurry. The supernatant was observed during irradiation of the zeolite immersed fully in seawater but not in case of the partial immersion.

Information gathering of working environment based on 3D reconstruction from plural images for decommissioning

Hanari, Toshihide; Kawabata, Kuniaki

no journal, , 

This paper describes our research on an environmental information gathering method of working environment based on 3D reconstruction from plural images for decommissioning work. We report on an application of 3D reconstruction method and post-processing for improving visibility of the environment model to the images from an underwater investigation task inside the Primary Containment Vessel.

Progress of 1F PCV contaminant analysis by TEM observation

Suzuki, Akihiro*; Kitsunai, Yuji*; Sato, Ikken

no journal, , 

Several contaminant samples from 1F1 primary containment vessel are carefully observed by transmission electron microscope to find micro-scale uranium-containing particles in their chemical forms of U-rich c-(U,Zr)O and Zr-rich t-(Zr,U)O, which are also observed in fuel debris of TMI-2 and Chernobyl NPP-4.